Perhaps you're confused, or your Putin admiration has you overlooking truth but Russia is more of a threat than the USSR ever was and it is closing in on superpower status. With their regional aggression in Georgia, Ukraine and threats to Finland the power of NATO and the permanent bases we maintain for first and counterstrike status in NATO counties are vital. That Putin supporters like Trump and his MAGA cultists want NATO neutralized is emblematic of their wanting America to lose it's status as the most powerful nation.
Your attempts at arguing why we she make ourselves more vulnerable by leaving a seventy year alliance are poor. European countries can and should spend more, yes, but that's not an excuse to leave NATO or for a madman like Trump to invite Russia to invade NATO member countries.